1. Field of the Invention
The present invention relates to a leak tester that injects pressurized air into an object that requires a sealing property and performs leak determination based on a change in the internal pressure after injecting the pressurized air, and also relates to an endoscope reprocessor.
2. Description of the Related Art
For example, endoscopes that are used in the medical field are subjected to a cleaning and disinfecting treatment after use to prevent infectious disease and the like. Since such kind of cleaning/disinfecting treatment generally uses a liquid, in a case where a sealing property of an endoscope is not maintained due to damage to an outer covering or due to looseness of a connection portion or the like, there is a risk of a liquid such as water or a cleaning liquid entering into the endoscope and causing a failure in an electrical system or the like such as an image pickup device. Therefore, a leak test needs to be carried out before performing a cleaning/disinfecting treatment on an endoscope.
As a method for automating leak determination on such an object that requires a sealing property, a technology is known which injects pressurized air into the object and performs leak determination by measuring a pressure change after allowing the object to stand for a fixed time period. In this case, after the pressurized air is injected, the internal pressure of the object changes not only when the pressurized air leaks but also when the pressurized air undergoes thermal contraction or thermal expansion due to a temperature change when the object is affected by the ambient temperature.
As technology for eliminating the effect of such disturbance and improving the accuracy of leak determination, for example, Japanese Patent Application Laid-Open Publication No. 2003-186551 discloses a technology that performs leak determination after controlling the temperature of an examination object by means of heated or cooled water so as to track the ambient temperature.